One
of the main pillars of computer science is the Church-Turing thesis,
which postulates that every classical system is equivalent, in terms
of computability power, to the so-called Turing machine. The
implications of this hypothesis in other scientific fields, however,
have hardly been explored. This is nonetheless a very natural
scenario since experimental setups are always controlled by computers
or other equivalent classical systems. In this talk I will show that,
in the context of quantum physics, computer science laws have
surprising implications for some of the most fundamental results of
the theory. In particular, I will show situations in which ensembles
of quantum states defining the same mixed state, indistinguishable
according to the quantum postulates, do become distinguishable when
prepared by a computer or, more generally, any device equivalent to a
Turing machine.